Design and development of fluted pumpkin (Telfairia occidentalis) leaves slicing machine

A motorized fluted pumpkin leaves slicer was designed, fabricated and tested. The machine comprises a conveyor system made from a rubber belt, two pairs of bearings and two hollow metal rods, a frame made from metal sheets for support. The slicing unit comprising the cutting blades and a drive (transmission) shaft, and finally a 746 W (1 hp) power drive mechanism (electric motor). Tests carried out on the machine involved placing 1 kg of fluted pumpkin leaves on the conveyor belt, which was then conveyed to the slicing unit, where it was chopped to desired size. It took an average of 9 minutes to process 1kg of the fluted pumpkin leaves during the test. Series of tests were carried out on the machine, which showed that it had an efficiency of 73.2% and is much faster than hand/manual slicing method.Keywords: design, development, fluted pumpkin, slicing machin

What Goes in Must Come out: Testing for Biases in Molecular Analysis of Arbuscular Mycorrhizal Fungal Communities

Arbuscular mycorrhizal (AM) fungi are widely distributed microbes that form obligate symbioses with the majority of terrestrial plants, altering nutrient transfers between soils and plants, thereby profoundly affecting plant growth and ecosystem properties. Molecular methods are commonly used in the study of AM fungal communities. However, the biases associated with PCR amplification of these organisms and their ability to be utilized quantitatively has never been fully tested. We used Terminal Restriction Fragment Length Polymorphism (TRFLP) analysis to characterise artificial community templates containing known quantities of defined AM fungal genotypes. This was compared to a parallel in silico analysis that predicted the results of this experiment in the absence of bias. The data suggest that when used quantitatively the TRFLP protocol tested is a powerful, repeatable method for AM fungal community analysis. However, we suggest some limitations to its use for population-level analyses. We found no evidence of PCR bias, supporting the quantitative use of other PCR-based methods for the study of AM fungi such as next generation amplicon sequencing. This finding greatly improves our confidence in methods that quantitatively examine AM fungal communities, providing a greater understanding of the ecology of these important fungi

The stage of soil development modulates rhizosphere effect along a High Arctic desert chronosequence

In mature soils, plant species and soil type determine the selection of root microbiota. Which of these two factors drives rhizosphere selection in barren substrates of developing desert soils has, however, not yet been established. Chronosequences of glacier forelands provide ideal natural environments to identify primary rhizosphere selection factors along the changing edaphic conditions of a developing soil. Here, we analyze changes in bacterial diversity in bulk soils and rhizospheres of a pioneer plant across a High Arctic glacier chronosequence. We show that the developmental stage of soil strongly modulates rhizosphere community assembly, even though plant-induced selection buffers the effect of changing edaphic factors. Bulk and rhizosphere soils host distinct bacterial communities that differentially vary along the chronosequence. Cation exchange capacity, exchangeable potassium, and metabolite concentration in the soil account for the rhizosphere bacterial diversity. Although the soil fraction (bulk soil and rhizosphere) explains up to 17.2% of the variation in bacterial microbiota, the soil developmental stage explains up to 47.7% of this variation. In addition, the operational taxonomic unit (OTU) co-occurrence network of the rhizosphere, whose complexity increases along the chronosequence, is loosely structured in barren compared with mature soils, corroborating our hypothesis that soil development tunes the rhizosphere effect

Bacterial Communities Involved in Soil Formation and PlantEstablishment Triggered by Pyrite Bioweathering on ArcticMoraines

Abstract In arctic glacier moraines, bioweathering primed by microbial iron oxidizers creates fertility gradients that accelerate soil development and plant establishment. With the aim of investigating the change of bacterial diversity in a pyrite-weathered gradient, we analyzed the composition of the bacterial communities involved in the process by sequencing 16S rRNA gene libraries from different biological soil crusts (BSC). Bacterial communities in three BSC of different morphology, located within 1 m distance downstream a pyritic conglomerate rock, were significantly diverse. The glacier moraine surrounding the weathered site showed wide phylogenetic diversity and high evenness with 15 represented bacterial classes, dominated by Alphaproteobacteria and pioneer Cyanobacteria colonizers. The bioweathered area showed the lowest diversity indexes and only nine bacterial families, largely dominated by Acidobacteriaceae and Acetobacteraceae typical of acidic environments, in accordance with the low pH of the BSC. In the weathered BSC, iron-oxidizing bacteria were cultivated, with counts decreasing along with the increase of distance from the rock, and nutrient release from the rock was revealed by environmental scanning electron microscopy-energy dispersive X-ray analyses. The vegetated area showed the presence of Actinomycetales, Verrucomicrobiales, Gemmatimonadales, Burkholderiales, and Rhizobiales, denoting a bacterial community typical of developed soils and indicating that the lithoid substrate of the bare moraine was here subjected to an accelerated colonization, driven by iron-oxidizing activity

Chemical composition of Dacyrodes edulis seed oil

Dacyrodes edulis seed were collected peeled, dried and powdered. The oil were extracted by simple method of cold extraction, the extracts were characterized by the Phytochemical analysis, Fourier transform infrared spectroscopy (FTIR) and Gas Chromatography (GC) to identify the fatty acid profile present in the seed oil. The FTIR analysis shows the variation of the peaks which indicate there is synergy among the functional groups of the extract. The phytochemical analysis revealed the presence of alkaloids, flavonoids, phenol, saponins, tannins and steroids, the study reveal the chemical constituents of Dacyrodes edulis seed oil that these constituents may be behind their medicinal values in phytomedicine

Calcineurin A-α suppression drives nuclear factor-κB-mediated NADPH oxidase-2 upregulation.

Calcineurin inhibitors (CNIs) are vital immunosuppressive therapies in the management of inflammatory conditions. A long-term consequence is nephrotoxicity. In the kidneys, the primary, catalytic calcineurin (CnA) isoforms are CnAα and CnAβ. Although the renal phenotype of CnAα and CnAβ. Although the renal phenotype of CnAα-/- mice substantially mirrors CNI-induced nephrotoxicity, the mechanisms downstream of CnAα are poorly understood. Since NADPH oxidase-2 (Nox2)-derived oxidative damage has been implicated in CNI-induced nephrotoxicity, we hypothesized that CnAα inhibition drives Nox2 upregulation and promotes oxidative stress. To test the hypothesis, Nox2 regulation was investigated in kidneys from CnAα-/-, CnAβ-/-, and wild-type (WT) littermate mice. To identify the downstream mediator of CnAα, nuclear factor of activated T cells (NFAT) and NF-κB regulation was examined. To test if Nox2 is transcriptionally regulated via a NF-κB pathway, CnAα-/- and WT renal fibroblasts were treated with the NF-κB inhibitor caffeic acid phenethyl ester. Our findings showed that cyclosporine A treatment induced Nox2 upregulation and oxidative stress. Furthermore, Nox2 upregulation and elevated ROS generation occurred only in CnAα-/- mice. In these mice, NF-κB but not NFAT activity was increased. In CnAα-/- renal fibroblasts, NF-κB inhibition prevented Nox2 upregulation and reactive oxygen species (ROS) generation. In conclusion, these findings indicate that 1) CnAα loss stimulates Nox2 upregulation, 2) NF-κB is a novel CnAα-regulated transcription factor, and 3) NF-κB mediates CnAα-induced Nox2 and ROS regulation. Our results demonstrate that CnAα plays a key role in Nox2 and ROS generation. Furthermore, these novel findings provide evidence of divergent CnA isoform signaling pathways. Finally, this study advocates for CnAα-sparing CNIs, ultimately circumventing the CNI nephrotoxicity.NEW & NOTEWORTHY A long-term consequence of calcineurin inhibitors (CNIs) is oxidative damage and nephrotoxicity. This study indicates that NF-κB is a novel calcineurin-regulated transcription factor that is activated with calcineurin inhibition, thereby driving oxidative damage in CNI nephropathy. These findings provide additional evidence of divergent calcineurin signaling pathways and suggest that selective CNIs could improve the long-term outcomes of patients by mitigating renal side effects

External Validation of Atherosclerotic Neuroimaging Biomarkers in Emergent Large‐Vessel Occlusion

Background Intracranial atherosclerosis related large vessel occlusion (ICAS‐LVO) is the major cause of failed mechanical thrombectomy. ICAS‐LVO causes reocclusion or a fixed focal stenosis, leading to suboptimal revascularization and poor functional outcomes. We aimed to externally validate 4 preidentified imaging biomarkers of ICAS‐LVO: absent hyperdense sign, Hounsfield units (Hu ratio ≤1.1 and Delta Hu <6) and truncal‐type occlusion, observed on admission noncontrast computed tomography and computed tomography angiography in patients presenting with emergent large‐vessel occlusion (ELVO). Methods We conducted a retrospective cohort observational study of consecutive patients presenting with acute M1/terminal internal carotid artery occlusions undergoing mechanical thrombectomy. Inability to locate a hyperdense vessel on noncontrast computed tomography at the corresponding ELVO on computed tomography angiography was labeled absent hyperdense sign. Delta Hu and Hu ratio were defined as the difference and ratio of the Hu of the ELVO on noncontrast computed tomography and its mirror contralateral patent vessel, respectively. ELVO was classified as truncal‐type occlusion if the bifurcation distal to the occlusion was spared on computed tomography angiography. ICAS‐LVO was defined as the presence of fixed focal stenosis or reocclusion after mechanical thrombectomy. Statistical analysis was performed using C statistics, receiver operating characteristic curve analysis, and multivariate logistic regression. Results Of 161 patients, 30 (18.6%) had suspected ICAS‐LVO. Absent hyperdense sign had a sensitivity of 90% and specificity of 87% (area under the curve [AUC], 0.88), in predicting ICAS‐LVO. Hu ratio ≤1.1 (AUC, 0.89) and Delta Hu <6 (AUC, 0.96) had sensitivity of 100% and 97% and specificity of 79% and 95%, respectively. Truncal‐type occlusion showed a sensitivity of 75% and specificity of 98% (AUC, 0.87). When comparing receiver operating characteristic AUC, Delta Hu <6 was significantly better than absent hyperdense sign (P=0.006); Hu ratio ≤1.1 (P=0.006); and truncal‐type occlusion (P=0.02). Conclusion Combination of neuroimaging biomarkers using noncontrast computed tomography and computed tomography angiography in ELVO identify ICAS‐LVO with high predictive power. Larger, prospective, multicenter studies are warranted to further evaluate their effectiveness in diagnosing ICAS‐LVO